Remote lamp control apparatus

ABSTRACT

A remote lamp control system for controlling the off/on status and dimming of the illumination in a high infrared and EMI noise environment is disclosed. The transmitted control signal is an infrared beam containing a selected pulse-time code which the receiving circuit can reliably receive, recognize and process in an environment of high infrared noise typically produced by fluorescent lighting. For the lighting fixture control, upon recognition and verification of the selected pulse-time code, the microcontroller outputs a signal to cause the lamp in the fixture to illuminate or go dark, or to change level of illumination. In preferred embodiments the detector for the infrared beam is in a grounded housing which is mounted in the lighting fixture, the cable connecting the detector to the microcontroller are all surrounded with an electrically conductive shielding which is grounded to the microcontroller.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority of U.S. Provisional Application Ser.No. 60/106,470, filed Oct. 30, 1998. This application is a divisionalapplication of U.S. application Ser. No. 10/077,401 filed Feb. 15, 2002,which is now U.S. Pat. No. 6,710,546; which is a divisional applicationof U.S. application Ser. No. 09/977,450 filed Oct. 15, 2001, which isnow U.S. Pat. No. 6,756,736; which is a divisional application of U.S.application Ser. No. 09/428,898 filed Oct. 28, 1999, which is now U.S.Pat. No. 6,392,349.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to the remote control of lighting systems such asemergency exit signs, on/off fluorescent lighting control, includingdimming and those lighting systems in high infrared or electromagneticinduction areas (including such as surgical suites and other medicalequipment areas), and particularly to areas having overhead fluorescentlighting.

Emergency lighting, including emergency exit lighting, is required incommercial, industrial, and institutional buildings just as fireextinguishers, smoke alarms and other safety equipment. Three types ofemergency lighting are common in such installations: unit equipment,engine generators and central battery systems. Unit equipment falls intotwo principle types: fluorescent and incandescent. Remote control oflighting systems, particularly those using infrared controllers commonto the remote control of electrical and electronic equipment such astelevision, video recording and stereo tuners, tape drives and compactdisk players are typically unreliable in environments with high ambientinfrared and electrically induced fields, rendering the convenience andcost effectiveness of such remote control systems unuseable in thesehigh electrically charged fields.

The emergency fluorescent units and exit sign systems are customarilycombined with and within a conventional fluorescent lighting unit(luminaire or sign) by merely adding the emergency ballast consisting ofa battery, a battery charger, inverter and sensing circuitry adjacentthe standard fluorescent ballast. The present invention is alsoadaptable to incandescent exit lighting which would include a rectifierand battery charger in lieu of the customary emergency fluorescentballast. In both applications, the sensing circuit observes theinterruption of normal AC power to the lamp unit and immediatelyswitches on the emergency power supply which powers the lamp for therequired period which, under most state safety codes, is a period of atleast ninety (90) minutes, a standard called out in the NationalElectrical Code, NFPA Article 70, and NFPA Article 101 Life Safety Code.These regulations at NFPA, Article 101, Section 5-9.3 also mandate thatperiodic monitoring of the ready status of the emergency systems,including a 30 day test requiring 30 seconds of lighting and annual testrequiring a 90 minute duration of lighting. An exception is provided forthose emergency lighting units which contain a selftesting/self-diagnostic circuit which automatically performs a minimum30 second test and diagnostic routine at least once every 30 days andindicates failures by a status indicator. U.S. Pat. No. 5,666,029assigned to the assignee of the present invention is illustrative ofsuch a self testing/self diagnostic circuit.

As is subsequently discussed, the remote transmitter and controlcircuitry including the microprocessor may be utilized to controllighting systems, such as on/off switching and in dimming control. Insuch applications, back-up power supplies are not necessary such thatthe control systems are less complicated.

2. General Background of the Invention

U.S. Pat. No. 5,004,953 entitled Emergency Lighting Ballast for CompactFluorescent Lamps with Integral Starters, assigned to the assignee ofthe present invention is illustrative of the fluorescent type ofemergency lighting with a ballast. It is common in the installation ofemergency fluorescent lighting that an emergency ballast is added to aconventional fluorescent fixture either in original installation or byretrofit. Alternatively, emergency lighting may be provided integrallyin a unit having both internal regular and emergency ballasts installed.When main AC power to the lighting fails, voltage sensing circuitryinstantly connects DC current from a battery (in the emergency ballast)to an inverter which produces high frequency, high voltage power toilluminate the emergency fluorescent lamp(s) for the required period.

The inclusion of test circuits for emergency fluorescent lighting iscommon, typically including the Test/Monitor panel, either mounted on awall in the building, generally adjacent the emergency lamp, or on thecase of the fluorescent ballast or fixture. The operation of these typesof testing circuits requires the technician to go to the particularlocation of the test switch for each emergency fixture, which issomewhat time consuming. Such a configuration involves considerableinstallation cost in that the wall mounted test switch must be wireddirectly to each fixture to be tested. In the case of test switcheslocated directly on a fixture, though avoiding the extra installationcost of the wall mounted switch, the technician then has to access eachfixture individually to initiate the test. This procedure is timeconsuming since fixtures are often eight to twenty feet above the floorin commercial or industrial buildings.

U.S. Pat. No. 5,455,487 entitled Moveable Desktop Light Controller isillustrative of systems for controlling the on/off status of a lightingsystem, such as a fluorescent lamp, and the control of the intensity oflighting by the inclusion of a dimmer for fluorescent lighting systems.The illustrated embodiments include such as a body heat detectinginfrared sensor and an ultrasonic motion detecting sensor for theinformation signal to control the lighting. The patent does not directlyindicate the specific type or nature of the “wireless” communication isutilized between the sensing device and the controller other thanproviding that the signal may be radio frequency or infrared. The '487patent makes reference to U.S. Pat. No. 5,189,393 entitled DualTechnology Motion Sensor which employs both ultrasonic and infrareddetection means to sense the presence of a human and trigger theillumination of area lighting. Dual signals are required to provideadditional reliability to the sensing to avoid false triggering of lamplighting.

U.S. Pat. No. 5,666,029 entitled Fluorescent Emergency Ballast SelfTestCircuit, assigned to the assignee of the present invention isillustrative of a fluorescent emergency lighting ballast which includesan integral self test function. In the described ballast, the testing isa programmed function, carried out independently by the circuitry in theballast and in the event of a malfunction in the test, a warning lightand/or alarm sounds to advise of the test malfunction.

The present invention in its most common form involves the combinationof the concept of a type of remote control as utilized with garage dooropeners, television and VCR machines which activates a specializedmonitor circuit integrally connected into the emergency ballast for thefluorescent emergency lamp, back-up power supply for exit lighting orthe lamp on/off and dimming control. In the case of the presentinvention including a remote control test feature, a technicianperforming the tests, whether the 30 second or the 90 minute variety,may conduct a survey of several emergency fixtures in a“point-click-test” series while making a tour through a facility,returning within the required time frame (30 seconds or 90 minutes) toobserve that the lamp is still operating in the emergency mode andmeeting the requirements of the Life Safety Code. For the emergency exitlighting, the test regimen may be analogous to the emergency lightingwith the test initiating signal providing the initiating signal specificto the exit system. In an alternative preferred embodiment, the testunit includes a reset function to terminate any unwanted prior testactivation. On reset, any prior test of the emergency ballast toemergency (i.e., battery) function is terminated and the lamp isreconnected to normal AC power, with the battery charging circuit alsoenergized. In those instances where the embodiment of the invention isutilized to control the on/off status of the lighting, or to exercisecontrol over the light output, as by dimming the lamp, the control isusable in a particular or multiple rooms for single or multiple lamps bymerely including a control message specific to the lamp or the room.

In the instances of use of the invention for control of a luminaire(incandescent or fluorescent) the IR transmitter is aimed at thedetector and similar point and click routine follows to turn theluminaire on or off, or to adjust the brightness of the illumination.The control is particularly effective and useful with fluorescent lightsor in areas of high ambient infrared or other EMI fields which otherwiseinterfere with conventional IR controls.

Prior attempts of providing fluorescent emergency lighting and similarhigh ambient infrared or similar electrical induced fields with suchremote control operation have been unsuccessful. The significant amountsof infrared light (noise) and induced fields produced by fluorescentlamps and related transformers interferes with conventional remotecontrol transmitters and receivers, to the degree that reliable,repeatable drive signals for tests and lamp control have not beenpossible. Further, the significant amount of infrared noise within theflourescent fixture has prevented the mounting of a useful detector ofthe remote test/control signal. The present invention breaks through theinfrared noise barrier by using a uniquely coded signal whichinterrogates the fixture and if analyzed to be of a proper digital pulsetrain, and upon successful match, initiates the particular requestedcontrol or test sequence (30 second or 90 minute) or mode of operationof the lamp. The invention further provides a novel infrared detectorhousing further enhancing the receipt of the coded signal and novelcabling to connect the detector to the control circuit in the emergencyballast.

SUMMARY OF THE INVENTION

It is an object of the present invention to perform selective testing ofan emergency power supply ballast of an emergency exit sign system.

A collateral object of the invention is to perform testing in theemergency power supply which closely simulates the emergency function ofthe exit sign lighting system, verifying that the emergency capabilityof the system is functional.

A further object of the invention is to provide for remote operation ofluminaires, particularly those located in and/or producing high ambientinfrared and/or electrical fields without having to directly activate aswitch or control located on the luminaire or at a discrete location.

These and other objects of the present invention are achieved by anemergency exit sign system including a luminaire with either afluorescent or incandescent lamp, means for delivering main AC power tothe lamp from an AC power source; a DC power source consisting of astored energy supply; rectifier means for recharging the stored energysupply; inverter means connected to the stored energy supply forproducing power from current provided by the DC power supply; supplyingsuch power to the lamp when the mains AC power is interrupted and meansfor deactivating the inverter when main AC power is being supplied tothe lamp; a remote infrared transmitter capable of emitting a codedsignal for interrogating an emergency system test control; an infrareddetector coupled to a microcontroller through a quick connect shieldedcable to receive, examine and decode the coded signal, themicrocontroller signaling the emergency stored energy supply to supplypower from the stored energy source by switching off the mains AC powerupon recognition of the coded test signal.

Further objects of the present invention are achieved by a luminairecontrol system including a luminaire with either a fluorescent orincandescent lamp, means for delivering main AC power to the lamp froman AC power source; a remote infrared transmitter capable of emitting acoded signal for interrogating the luminaire system control; an infrareddetector coupled to a microcontroller through a quick connect shieldedcable to receive, examine and decode the coded signal, themicrocontroller signaling the luminaire control to initiate the on/offstatus of the luminaire and/or signaling the dimming or brighteningstatus of the luminaire by activating the relevant control uponrecognition of a particular coded signal.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a circuit diagram of a preferred embodiment of the remotecontrol test for fluorescent emergency lighting according to the presentinvention including the infrared initiated microcontroller circuit foractivating a remote control test.

FIG. 2 is a flow chart illustrating the test procedure according to thepresent invention.

FIG. 3 is a diagram of the code signal transmitted by the remote controltransmitter and received and processed by the microcontroller circuit inthe present invention.

FIG. 4 is a perspective view of a strip fluorescent fixture includingthe present invention.

FIG. 5 is a perspective view of a troffer fluorescent fixture includingthe present invention.

FIG. 6 is a top view of the cable assembly according to the presentinvention.

FIG. 7 is a perspective view of a troffer fixture with the lens openillustrating the present invention.

FIG. 8 is a partial sectional view of the mounting of the cable assemblyof the present invention in a troffer fixture.

FIG. 9 is an additional partial sectional view of the mounting of thecable assembly of the present invention in a troffer fixture.

FIG. 10 is a pictorial view of a strip fluorescent fixture, partiallycut away, illustrating the present invention.

FIG. 11 is a sectional view of the detector housing according to thepresent invention.

FIG. 12 is a pictorial of the detector housing of FIG. 11.

FIG. 13 is an elevational view of the detector housing of FIG. 11.

FIG. 14 is a sectional view of the detector housing of FIG. 13, taken online AA.

FIG. 15 is a plan view of the lens cover for the detector housing ofFIG. 11.

FIG. 16 is a block diagram of an alternative embodiment of the inventionfor emergency exit sign testing.

FIG. 17 is block diagram of an alternative embodiment of the inventionfor controlling the on/off stat of a lamp.

FIG. 18 is a block diagram of an alternative embodiment of the inventionfor controlling the brightness of the illumination of a lamp.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIGS. 1, 4, 5, 7 and 10, the invention is illustratedin the context of a remotely controlled test system for conventionalfluorescent lamp (whether a strip fixture 10 or a troffer fixture 12),including an emergency ballast 14 for standby lighting during a periodwhen the main AC power fails. Variations of the preferred embodimentsfor Emergency Exit Sign Systems, “On/Off” Lighting Control and LightDimming Control which are subsequently described, the differences inapplication are directed to the particular mode of operation of the signor luminaire with only minor changes of the interface between the remotecontrol transmitter and the controller circuit, including themicrocontroller.

FIG. 1 illustrates the circuit diagram of a conventional emergencyballast which would be connected in parallel with a conventionalfluorescent ballast 16 for providing emergency lighting in the event ofmain AC power failure. In the FIG. 1, were the standard fluorescentballast be shown, its output would be connected to lamp(s) LAMP, inparallel with the output of the emergency ballast EMERG. Relay contactsK2 and K3 operated by coils K2 and K3 are responsive to the battery BATTcharging current and upon failure of the main AC power, failure of powerto the battery charging circuit In, and thus K2 and K3, allows theswitching of the relay contacts K2, K3, to shift the load of LAMP fromthe AC supply (via the standard ballast) to the emergency ballast EMERG.More particularly, as described below input/charging circuit In whichprovides charging current to the battery BATT and disables the emergencyoperation mode of the emergency ballast EMERG during the period that ACpower is being supplied by main AC supply, as at J11 or J12 and J13. Inpreferred embodiments of emergency ballasts, inclusion of alternativevoltage connections enable the system to be selectively connected toeither standard commercial voltage AC (277 volts AC) or normalresidential voltage (120 volts AC). Common, or ground potentialconnector J13 completes the connections to the system input. For afluorescent exit sign installation, the circuitry would be similar andthe lamp LAMP would be a fluorescent lamp providing the sign lighting“EXIT” rather than illumination of the surrounding area. For anincandescent exit lamp sign, the battery and charge circuit wouldreflect the electrical demands to power the lamb (i.e., voltage andamperage). For the luminaire control embodiments (incandescent orfluorescent) the standby power supply including such as the battery andcharging circuit, would not be included.

The two voltage terminals and the common terminal are connected to theAC inputs of a full wave (preferably) rectifier D6, the high voltageinput terminal being connected via capacitors C1 and C4 and resistors R8and R7 to limit the charging current supplied to rectifier D6 todischarge the power from the capacitors after the power is removed fromthe circuits. The DC output from rectifier D6 is supplied to batteryBATT via the coils of relays K1, K2 and K3. Similarly, the DC output ofrectifier D6 is connected to a light emitting diode LED as an indicatorthat the battery BATT is in the charging mode.

Responsive to the status of input/charging circuit In, the switch ofrelay, K2, which is connected to terminal J27, and to a normally opencontact (NO) of relay, K2, when its coil is energized and to terminalJ25, a normally closed contact (NC) of relay K2 when its coil isde-energized, the latter position being that illustrated in FIG. 1.Relay K3 has a similar switch and associated set of contacts which areprovided to connect load LAMP when the normal AC supply or auxiliary ACsupply is powering the input/charging circuit In.

Battery BATT may be composed of, for example, a 6 volt (DC) nickelcadmium battery. Alternate battery configurations are possible, dictatedby the power requirements of load LAMP. The output circuit O of theemergency ballast EMERG includes a transformer T1 having a primarywinding P1 and a feedback winding F1 on the input side of transformer T1and a secondary winding S1 on the output side. Output circuit O providescurrent limiting to the fluorescent lamp load LAMP only to the degreethat is necessary to keep a fluorescent lamp within its operationallimits. The output circuit O is composed of a capacitor, C5, connectedacross the output of the secondary winding, S1, of transformer T1.Capacitors C6 and C7 connected in parallel and generally in series withthe fluorescent lamp LAMP which the output circuit O powers duringemergency operation.

In the emergency mode, power is supplied to load LAMP from the outputcircuit by battery BATT through the operation of inverter circuit Iv.Initially the operation of the inverter circuit Iv is placed inoperation by transistor Q3 going into conduction enabling theoscillation of switching transistors Q1 and Q2, including a high voltagesurge from the output circuit O for a short interval (which may be inthe order of a few milliseconds) after AC power failure to permit thestarting of the fluorescent lamp. Those familiar with fluorescentlighting will recognize that a short application of an initial voltagein the range of approximately 500 volts is required to initiate theignition of the gasses in the standard fluorescent lamp. Immediatelyafter ignition, as switch Q3 continues to supply base current to Q1 andQ2 as later discussed, the current regulating capacitors C8 and C7 inthe output circuit O regulate the current level to that required tooperate the fluorescent lamp at its emergency rated (reduced)illumination.

During normal operation when main AC power supply is functioning,charging current is supplied from the rectifier D6, to battery BATT,while energizing relays K1 and K2 so that the switch Q3 and theoscillating switches Q1 and Q2 and the output circuit O are inactive.Should the main AC power supply fail, and for that continuing period oftime until normal main AC power resumes, such that its frequency andvoltage output again power rectifier D6, relays K1 and K2 arede-energized so that the fluorescent lamp load is connected to theoutput circuit O and the inverter Iv is triggered into operation.

Remote Control Test Circuit (RCT) as utilized in the testing ofemergency lighting, whether luminaire or exit sign, is connected to theemergency ballast EMERG through terminal J1-6, which is tied to theoutput of rectifier D6 at diode D1. In order to initiate a test of thefunction of the emergency ballast, the output on pin GPO onmicrocontroller MC of the RCT activates switch Q201 which sinks thecurrent coming out of rectifier D6 through resistor R2 causing thebattery charging circuit In to sense a failure of main AC power. Then,according the description of the RCT circuit below, the emergencyballast EMERG cycles through a 30 second or a 90 minute test, assignaled by the RCT.

As illustrated in FIG. 1, RCT is driven by a microcontroller chip MC,such as the PIC12C508 from Microchip, Inc. which is utilized in theillustrated embodiment. As those skilled in the art will appreciate, theselection of a particular microprocessor is influenced by the functionsto be performed, costs and compatibility with the other systemcomponents, and other microcontrollers might be selected, with someadjustment of other circuit components. RCT is powered by emergencyballast EMERG through contacts J1-1 from battery BATT which is providedto regulator U201 which provides a regulated 5 volt supply to themicrocontroller chip MC and to an infrared detector ID, which is mountedon the face of a fluorescent fixture or, in the case of a ceiling mountwith a translucent cover, on the face of the cover adjacent the fixturebehind the cover (not shown). Infrared detector ID receives a codedsignal (described later) from the remote transmitter which is suppliedto the base of buffer Q202 which inverts and amplifies the receivedcoded signal and inputs the signal to the microcontroller MC at pin GP1.Microcontroller is driven by resonator RES, which in the illustratedembodiment includes capacitors C206 and C205, R205 and resonator Y201which sets the clock frequency of microcontroller MC at 2 MHZ, a valuecoordinated to the signal received from infrared detector ID to beexamined and processed by microcontroller MC. As observed previously,those skilled in the art should understand that the clock value might bevaried should a different coded signal or other operating parameter bechosen.

As added reliability for the testing process available through theremote control test circuit RCT, a reset capability is supplied by areset control RS including undervoltage sensing integrated circuit U203(such as MC34164). Reset RS monitors the battery BATT voltage (the 5volt output voltage of regulator U201) and is set to signal a supplyvoltage of less than 2.7 volts, selected as the lower limit ofreliability for signal processing by microcontroller MC. On observationof a supply voltage of below 2.7 volts, reset RS provides an input tomicrocontroller MC pin MCLR which in the preferred embodimentillustrated disables the microcontroller MC. When reset RS observes thatthe supply voltage has returned (i.e., above 2.7 volts), it outputs asignal through resistor R204 to pin VDD to recycle or “wake up” themicrocontroller MC such that any incoming signals from infrared detectorID may be again processed.

Wherein the remote control transmitter 22 and the remote control testcircuit RCT are modified for control of a luminaire not requiring a testof an internal battery supply, those skilled in the art will recognizethat the related control aspects of the microcontroller MC may beomitted. The remaining essential functions in respect of the generationand recognition of the coded signal and the directing of the relevantcollateral function as “OFF, ON” and adjustment of the brightness ofillumination become the object of a selected signal. Accordingly themicrocontroller MC is adapted to provide an output to an electricallycontrolled switch (ON/OFF) or to an electrically controlled dimmer, suchas a potentiometer for an incandescent or a variable ballast for afluorescent lamp. (All subsequently described in conjunction with FIGS.17 and 18).

FIG. 2 illustrates the interrogating signals transmitted by thehand-held remote (not shown) which are received by the infrared detectorID (20 in FIGS. 4, 5, 7, 8, 9, 10 and 11). The carrier frequency for theremote communications is centered at 319 THz, which is in the infraredspectrum (λ=950 nm). This carrier is amplitude modulated by a 38 KHz subcarrier in digital (on-off) pulses. This type of modulation is termedAmplitude Shift Keying modulation and significantly reduces thepossibility of interference from other infrared sources, particularlythe fluorescent lamps in close proximity to the testing process. Theon-off digital pulses form a code modulation method of Pulse Codemodulation (PCM) and the series of pulses convey the informationrespecting to the particular test to be performed. In the preferredembodiment illustrates, the signal incorporates a Pulse-Timingmodulation (PTM) of a serial bit pulse train of nine bits, one start bitfollowed by eight data bits. These bits (again in this preferredembodiment) are 2.11 ms apart (at 473.9 Hz) with an “ON” pulse width of0.817 ms, yielding a duty cycle of 38.7 percent. The 9-bit cycle isfollowed by a break, in the preferred embodiment of 31.6 ms.Accordingly, the entire signal (data plus break) is repeated every 49.27ms as long as a selected transmit key on the hand-held remote isactivated. It is significant to the reliability and repeatability of theinventive test that the complexity of both Pulse Code and Pulse Timingmodulation are combined, the effect of which is to increase thesignal-to-noise ratio of the interrogation to ensure accuracy andreliability of test. By using the described approach including amicrocontroller in combination with the infrared detector to decode thetest signal, the use of expensive and massive “matched filter” isotherwise avoided. Further, the use of the low frequency bit rateenables the signal to be checked for time “on” as well as time “off”,along with the check of the bit pattern correctness, all withoutexcessive demands on the decoding and thus reducing cost of the circuit.It should be appreciated by those skilled in the art that other infraredwavelengths than the illustrated and described 950 nanometers maydetermine the base frequency upon which the test/control signalingsystem of the present invention may operate. Any convenient wavelengthhaving a carrier frequency in which the wavelength is in the range ofabout 770 nanometers to about 100,000 nanometers (the recognized bandfor infrared energy) may be chosen. As indicated above, efficiencies aregained by picking the carrier frequency according to those electroniccomponents which are readily available, as being regularly stocked byone or more providers. For example, remote control detector supplierscarry components with sub-carrier frequencies in the 30 to 60 KHz range,with the most common frequencies being in the 38 to 40 KHz range.Detectors with sub-carriers at frequencies around 500 KHz are alsoreadily available. These latter components are common in infraredcontrols for computers for such as mouse control and visualpresentations.

FIG. 3 illustrates three different signal lines for the describedembodiment utilizing a detector and related components operating at 950nanometers wavelength, one for the 30 second test wherein the emergencyballast is signaled on for the 30 second period to assure operation ofthe fluorescent lamp in that period. The second signal line initiatesthe 90 minute test wherein the emergency ballast is controlled in the oncondition for a period of 90 minutes to verify that the emergencylighting (and the battery capacity) will continue lighting in theemergency mode for that period. The third signal is to provide a resetof the system (and the emergency ballast) back to the regular operatingcondition wherein the lighting is powered by the main AC supply throughthe standard ballast, and the emergency ballast is in standby conditionwith its battery being charged. Those skilled in the art shouldrecognize that in the alternative embodiments later described, the firstsignal could be the lamp “ON” signal, the second signal the lamp “OFF”signal and the third and an added fourth signal might function as theraise and lower commands for the dimming circuit. The reset signal isused primarily to terminate a running test, should that be desired. Themicrocontroller clock times each test and terminates the procedure atthe end of the requisite time (i.e., 30 seconds or 90 minutes.) Thehand-held remote control transmitter is analogous to the remote controlsfor television and video recorders, however wherein a preprogramed ICselectively transmits the signal pulse words illustrated in FIG. 3according to the activation of the operating switches located on thehand-held control. The preferred hand-held control includes the capacityto selectively transmit one of the three pulse-time signals, each ofwhich is dedicated to one of the three command functions of thehand-held remote: a) the 30 second test; b) the 90 minute test; and c)the reset signal. Similarly to the television remote, the transmitter isaimed at the detector D (18 in FIGS. 4, 5) in the fluorescent fixture(10, 12 in FIGS. 4, 5), such that the selected infrared pulse train isbeamed at the detector housing 20. Upon receipt of the signal, it isprocessed as described above. As previously stated, it is viewed aswithin the skill of the art to adapt the present pulse train fordifferent or additional control signals and to adapt the base frequencyor the carrier frequency to operate at different levels.

The inventive signal code and timing together with the inventiveelements described below enable the effective use of relativeinexpensive, easily installed and used infrared signal interrogation anddecoding within a high infrared noise environment and electromagneticfields, thereby enabling the use of low cost infrared remote technologyanalogous to that used in TV's and VCR's, which otherwise would beunusable. The inventive detector housing 20 and shielded cable assembly23 enable the more reliable use of the infrared signal code and timingin the noisy infrared environment. By way of general explanation of theinterrogation process, prior to the full explanation of the flow diagramof FIG. 3, in the process of interrogation, the start bit is checked fora correct “ON” time and then checked for a correct “OFF” time. If thisstart bit is recognized as a correct bit, then the remaining eight bitsare checked for the correct “ON” and “OFF” times, or are read andidentified as one of the three signal train streams. Once the decodedpattern is verified as one of the three proper signals, themicrocontroller looks for a second stream of bit information, to verifyit as correct and a match of the first signal stream. Thus, the signalinterrogation is checked for correctness in format based upon time, dutycycle and matching (twice) one of the three coded patterns. Theinventive methodology provides sufficient signal-to-noise response toprevent false triggering of the test procedure by random infrared noisesignals.

As illustrated in the flowchart of FIG. 2 for testing proper emergencylamp and exit sign function, on START, the microcontroller clock iscleared, ready for the start of the interrogation process. OnINITIALIZATION the software in the microcontroller sets up the memorymap and counters to prepare the sequence of functions to be performed bythe controller. When the memory map and counters are installed, CLEARsets the status register. CHECK is a verification that themicrocontroller is set up and keeps up with time after which it SCANsthe signal from the infrared detector ID to verify the receiving signalis at the required voltage level for processing; if it is (GP1 HIGH) theprocessing continues, if not, the microcontroller continues to examineincoming signals to look for one of the requisite voltage. With therecognition of a signal of sufficient voltage, COLLECT START BIT DATAreceives the first data bit which in GOOD START BIT is checked forproper timing and width, and if the criteria are met (yes) theprocessing continues. If the start bit fails, the microcontrollerresumes looking for a proper signal, clearing all stored signal memoryat CLEAR. Once the suitable start bit is recognized, the microcontrollerat COLLECT BODY DATA receives the remainder (8 bits) of the signal andexamines the string to verify (CHECK) that eight additional bits werereceived. The microcontroller then in DECIFER does a more detailedreview of the signal string to verify that the first bit is a true firstbit (time and pulse width) and (CHECK) that there are eight correctfollowing bits. If the CHECK is passed, BODY OF WORD GOOD is the secondcheck on the following string of data bits to verify that the examinedsignal was repeated and matched. If this WORD is matched to one of thethree words, the microprocessor then (on yes) proceeds to the test; ifnot, the process goes back to the CLEAR, clearing out stored signalmemory and looking again for a proper first bit. At TEST IN PROGRESS themicrocontroller reads its activity to determine whether there is a testalready ongoing; if so, the START ABORT function reads the word to seeif it is the RESET signal, in which case the RUN ABORT SEQUENCEterminates the running test and sends the process back to the CLEARfunction. With no test in progress, the particular bit word is examinedto determine whether a 30 second or a ninety minute test is called for.On the particular recognition, either the 30 SECOND TEST or the 90MINUTE TEST initiates the appropriate test sequence, including TURN LAMPON for the requisite period and after the running of the program, or theabort sequence, the microcontroller returns to CLEAR for another signal.

Referring now generally to FIGS. 4 through 15, one important objectiveof the present invention as applied to emergency exit systems is toallow the technician to aim the Remote Control Transmitter 22 (FIGS. 4and 5) toward the lighting fixture 10, 12 and energize the test routinepreferred. Because of safety requirements such as those imposed forapproval by Underwriters Laboratories or by various electrical codes,the detector and the wires connecting the infrared detector to theRemote Control Test Circuit (RCT in FIG. 1) may have to be placedtotally within the sign fixture or, run through electrical conduit(which is costly, and would be cumbersome in installation). Therefore,placement of an infrared detector housing 20 around or behind the sign(equivalent to troffer fixture 12 in FIGS. 5 and 7). It is well known tothose skilled in the art relating to infrared remote controls such asfor television and video recorders that fluorescent lighting generatessignificant infrared noise which interferes with the communicationsignals of infrared controllers. It is for this reason that infraredremote controllers are not utilized in close proximity to fluorescentlighting or where high infrared or other EMI fields are presents. Thereis an added complication in the fluorescent lighting application sincethe detector may be located behind fixture lens 24 (the function ofwhich is to diffuse the fluorescent light generated) so the fixture lens24 further diffuses the signal from the Remote Control Transmitter 22before it is received by the detector 18 in detector housing 20 as wellas reflecting some of the infrared noise generated by the fluorescentlight back toward the detector 18. A further factor complicating the useof infrared detectors in such as fluorescent lighting is theelectromagnetic fields generated by the high frequency electronicconventional 16 and emergency ballasts 14 which are in close proximityto a detector housing 20 mounted within a light fixture 10, 12. Thepresent invention enables the use of infrared remote controllers infields having a high degree of infrared noise, even when associatedcomponents generate electromagnetic fields, techniques previouslyavoided by those skilled in the art.

Referring now specifically to FIGS. 4 through 15, in addition to the useof a specially coded signal which is verified by a second signal trainas discussed above, the present invention includes a novel detectorhousing 20 in which an infrared detector unit 18, such as a GP1U901Xinfrared detector from Sharp Electronics, Inc., is mounted. Thepreferred detector is compact in size to be conveniently located withinthe flourescent fixture 10, 12 or the fixture of an emergency sign.Detector 18 is mounted in a housing 20 which is also sized to beconveniently placed within a fluorescent fixture or the emergency sign.In the preferred embodiment illustrated, detector housing 20 iscomprised of two adjoining cylindrical sections, a collar section 21 anda detector section 28. Being adapted for mounting directly into standardfixtures as strip 10 and troffer 12, collar section is approximately ½inch in diameter to fit a standard ½ inch electrical mounting tube 26for the troffer mounting illustrated in FIGS. 8 and 9. Tube 26 isretained in fixture 12 by means such as bracket 19 conveniently locatednear the end of fixture as illustrated in FIG. 5. For mounting in astrip fixture 10 having standard ⅝ inch holes, the detector section 28has an outside diameter of approximately ⅝ inch. Housing 20 ismanufactured of a convenient, light weight material such as PVC, eitherby fabrication or molding. Other materials, including metals might besubstituted, depending upon cost of materials and manufacture. Thedisclosed embodiment of detector 18 and detector housing 20 are alsoparticularly effective for controlling a fluorescent luminaire, or anincandescent lamp located in high EMI field areas such as hospitalsurgical suites and the like.

The preferred detector 18 is capable of receiving the interrogatingsignals from the Remote Control Transmitter 22 and generating acomparable signal which is passed on to the remote control test circuit(RCT in FIG. 1) which is physically located in the emergency ballast 14.Detector 18 operates on the Amplitude Shift Keying (ASK) code principleand incorporates a 38 kHz bandpass filter with high-gain amplifiers andan automatic gain control (AGC), parameters matching the interrogatingsignal from the Remote Control Transmitter 22. Contributing to thespecial effectiveness of the present invention is the configuration ofthe detector housing 20. As maybe seen in FIGS. 12 through 15, housing20 includes collar section 21 sized to conveniently receive cable 27which connects detector 18 to the remote control test circuit RCT (FIG.1). Cable 27 is preferably shielded to minimize electromagneticinduction from the fields established by the conventional and emergencyballasts. Further, cable 27 is sealed into the inside diameter 25 ofcollar 21 with potting 31, such as a silicon compound, for strain reliefbetween the cable and collar section internal diameter 25. Detector 18is mounted into the detector section 28 of housing 20, being affixedwith a suitable adhesive to a mounting platform such as the off-set 30between the different inside diameters 29, 25 of the collar section 21and the detector section 28, respectively. Other techniques for mountingthe detector 18 within housing 20 may be employed subject to location ofthe receiving eye 32 of detector 18 within detector section 28 so as tohave an angle of incidence α which shadows or blocks substantial amountsthe surrounding detrimental infrared noise by limiting the reception ofthe eye 32 to a convenient cone within the angle α. Those skilled in theart will appreciate that the angle of incidence α of receiving eye 32 isdetermined by the depth of eye 32 within the inside diameter 29 ofdetector section 28 as well as the detector section inside diameter 29.

An additional aspect of the present invention includes shielding 34around the interior diameter 29 of the detector section 28. Shielding 34is of an electrically conductive material, such as an adhesive backedcopper tape such as produced by Minnesota Mining and Manufacturing, Inc.and available from electrical supply houses. Other shielding materialsmay be used so long as they are attachable to the interior diameter ofdetector section 28. In the present embodiment, shielding 34 isconnected at terminal 36 to the ground wire 27 d for cable 27 which isalso shielded (not shown) and similarly connected to detector housing 20at terminal 37 to protect against the electromagnetic field establishedby and in the vicinity of the electronic ballasts for the fluorescentlamps. In the preferred embodiment described, the Sharp GPIU901X isenclosed in a metal case or housing 18 h so that the detector 18electronics are also shielded from the electromagnetic field of theballasts. Since both housing 20 and cable 27 are shielded against theelectromagnetic field interference, both may be mounted within the bodyof lighting fixtures 10, 12. Completing the assembly of detector housing20 is the lens cover 46 which covers and protects the sensitive infrareddetector 18 from dust or other airborne particles which may be presentin a commercial or industrial environment. Lens cover 46 is preferablywhite so as to be relatively unnoticeable under fixture lens 24 whenclosed. Cover 46 is composed of a material which is translucent ortransparent to the infrared signal from remote control 22, such as of arigid vinyl or MYLAR, a polyester material available from E. I. duPontde Nemours & Company. Lens cover 46 material is selected to provideminimal attenuation of the infrared test initiating signal from RemoteControl Transmitter since the less attenuation caused by lens cover 46,the greater will be the strength of the test initiating signal whichmust be received through the infrared noise by detector eye 32. Lenscover 36 is retained on detector section 28 by means such as an adhesiveor other suitable attachment mechanism.

Completing the mounted assemblage for mounting a remote control testmodule including an infrared detector is cable assembly 23 (FIG. 6)including cable 27 being a three wire shielded cable such as Belden 9533060 which is fitted at one end with a miniaturized, three prongplug-type connector 33 such as Berg 67954-002. It is preferable toenclose the connector 33 and attached (as by soldering or crimping)wires 27 r, 27 w, and 27 b in such as stress relieving sleeve 35, (i.e.,heat shrink tubing from SPC Technology PHS-024) to ensure reliableperformance. Cable assembly 23 is terminated at its other end bydetector housing 20 including detector 18. Cable wires 27 r and 27 wterminate on terminals 37 t of detector 18 and carry the signal outputof detector 18 responsive to Remote Control Transmitter 22 test signalsto the remote control test circuit RCT (illustrated in FIG. 1). Wire 27b and the cable shield drain 27 d are terminated on the casing 18 h ofdetector 18 at terminal 37 and drain 27 d is also terminated on detectorshield 34 at terminal 6(all illustrated in FIG. 11). As with connector33, the termination of wires 27 r and 27 w at detector 18 includesstress relieving sleeve 38, preferably of such as heat shrink tubing(e.g., 3M FP301). For ease of installation of the remote control testfeature in the field, it is preferable to provide emergency ballast 14with a complementary cable assemble 23′ (to assembly 23) which isconnected to the test circuit RCT (FIG. 1), and a cooperating femaleplug 33′ (e.g., Berg 67954-00) to plug 33 so that the cables 23, 23′need only to be connected, as at connection 40 in FIG. 9.

Referring now to FIG. 16, the alternative embodiment of the presentinvention as applied to emergency exit signs is illustrated. Emergencyexit signs incorporate many components similar to emergency lightingsystems. Such systems incorporate a battery and rectifier circuit, apower supply such as an input of normal AC power AC_(In), a lightsource, and a means such as lamp driver LD to automatically switch overto emergency mode. The battery is charged by a battery charger BR andkept ready to supply energy power to a lamp power supply LD upon powerfailure. The power supply is specific to the lamp load. In fluorescentlamp systems, this power supply is a fluorescent lamp ballast asillustrated and described above. In systems incorporating incandescentlamps, this power supply might simply be a DC voltage source capable ofsupplying lamp current for the requisite time. In any exit sign system,there needs to be a means of testing the individual emergency exit signsfor readiness. The proper test(s) involves momentarily removing electricpower from the unit to simulate a power failure. This forces the unitinto emergency mode, where the battery, lamp, and entire exit signproduct is tested for its capability to light when AC power is removed.The test should be performed periodically in compliance with localsafety code requirements and should last for a pre-determined amount oftime, consistent with code requirements. In conventional exit signs,such a switch is merely a push button switch to momentarily test to seethat the sign remains illuminated by a back-up battery supply.

The present invention can be used to activate an in-line power switchS_(T) (such as a relay) to momentarily break power to the exit sign,forcing it into the emergency mode. In a mode similar to that describedfor emergency lighting, above, the present invention can control theduration time of the test to comply with the local safety coderequirements. Test duration time(s) are pre-programmed into themicrocontroller MC to provide an output responsive only to a repeatedselected pulse-time coded infrared signal (analogous to the coded signaldescribed above). Each of the remote control transmitter 22 (FIGS. 5 and16) designated push switches (analogous to the channel numbers on a TVremote control) activates a pre-programmed code that is sent to theselected infrared detector 18, mounted in or near the exit sign. Theinfrared detector 18 is adapted with a shielded housing 20 to reduce EMIand IR noise (as illustrated in FIGS. 11-15 and text relevant thereto).Since the present invention uses IR technology, the test can be madespecific to the individual exit sign that is aimed at by thetransmitter; thereby, avoiding unintended test activation of nearby exitsigns.

The advantage of present invention as applied to exit signs is toprovide a convenient, reliable and safe means to perform the test. Thistesting procedure becomes as easy and simple as changing the channels ona remote TV. This avoids the cumbersome use of climbing a ladder anddepressing and holding a manual momentary test switch. The presentinvention also allows for easy testing of difficult to reach exit signs,such as, exit sings near stairwells, exit signs that are high above afloor, and exit signs that are in other difficult to reach places.

Alternative embodiments of the present invention incorporated intosystems for controlling lamps and luminaires as are illustrated in FIGS.17 and 18 and subsequently described. The present invention in analternative embodiment may be used to remotely perform the simple taskof turning individual light fixtures on and off at will. (See FIGS. 1and 17) The remote control transmitter 22 can be used to activate anin-line power switch S_(W) (such as by a relay) to break power to a lampor light fixture LAMP; thus, turning it off. Likewise, the remotecontrol transmitter 22 can be used to activate the in-line power switchS_(W) to restore power to the light fixture; thus, turning it back on.The remote control, switch control C_(S) can also be used to control theon or off time by pre-programming into the microcontroller MC containedwithin switch control C_(S) as the pre-determined “on” or “off” timefunction responsive only to a repeated selected pulse-time codedinfrared signal. Each of the remote control push keys (when depressed)activates and transmits a distinct pre-programmed code that is sent tothe infrared detector 18. The code that correlates to the particularfunction designated for an individual push key corresponds to one of thepre-determined on or off times. The microcontroller MC may be similar tothe unit MC illustrated and described in connection with FIG. 1, above.

The present invention offers a specific advantage for remote control offluorescent light fixtures because an embodiment of the invention isparticularly immune to IR and EMI noise generated by components in thesefixtures. The infrared detector is adapted with a shielded housing andplacement optimized to reduce EMI and IR noise. The infrared detector 18would be mounted in or near the target light fixture. Since the remotecontrol uses IR technology, it is an alternative to remote control usingRF, where the use of RF might pose interference problems to sensitiveequipment such as medical equipment.

Light dimming may also be accomplished using the hand held remotecontrol transmitter 22 according to the present invention to operate thedimming control C_(E) of the light fixture LAMP. (See FIGS. 1 and 18)Dimming levels are pre-programmed into the microcontroller MC locatedusually at the light fixture in a remote control circuit C_(S) whichprovides an output responsive only to a distinct, repeated selectedpulse-time coded infrared signal sent by the remote transmitter 22. Eachof the remote control push switches activates a one of the distinctpre-programmed codes that is sent to the infrared detector 18, mountedin or near the light fixture LAMP. The infrared detector 18 is adaptedwith in a shielded housing 20 to reduce EMI and IR noise, which istypically present in fluorescent lights. One key advantage of remotecontrol of the present invention is that it provides a convenient,portable means to remotely perform dimming of individual luminaires inhigh EMI and IR noise environments such as fluorescent lightingenvironments. Another key advantage is the use of IR technology, whichis an alternative to remote control using RF, which is particularlyadvantageous where the use of RF transmission might pose interferenceproblems to sensitive equipment such as medical equipment or othersystems control apparatus. Furthermore, since the inventive controlleruses IR technology, dimming can be made specific to an individual lightfixture within the transmitted signal beam that is directed by thetransmitter; thereby, avoiding unintended activation of nearby lightfixtures.

While the present control is described in terms of a fluorescent lamphaving an internal electronic control ballast, the present invention maybe adapted with any electrical or electronic dimming control whichadjusts the brightness of illumination of a lamp such as an incandescentor high intensity/high intensity gas filled lamp.

PARTS LIST

In the illustrated embodiment, the following components have the valuesindicated:

C1 6.8 μFd C4 4.7 μFd C5 220 μFd C6 1000 ρFd C7 680 ρFd C8 1500 ρFd C204.7 μFd C201 0.1 μFd. C202 0.1 μFd. C203 15 μFd. TANT C204 0.1 μFd. Q1NPN transistor D44H8 Q2 NPN transistor D44H8 Q3 PNP transistor 2N4403PNP Q201 NPN transistor ZTX851 Q202 NPN transistor ZTX851 U201 Regulator5 V. TK11650 U202 Microcontroller PIC12C508 U203 Reset MC34164 Y201 2MHZ resonator R2 10M ohms R3 180 ohms R4 120 ohms R5 15k ohms R6 1K ohmsR7 10M ohms R8 10M ohms R15 15K ohms R20 4.7K ohms D1 Diode 1N4005 D3Zener 1N5347 D6 Bridge D7 Diode 1N4005 D8 ZENER 1N5221B D9 High VoltageDiode 2000 VDC, 50 mA, BYD43X2 D10 High Voltage Diode 2000 VDC, 50 mA,BYD43X2 D14 Diode 1N4005 K1, K2, K3 Relay SPDT 75 mA., 6 V. TTransformer S1 500 turns, 34 ga. P1, 6 turns, center tapped, 23 ga. F1 2turns, 23 ga. Core ferrite plus BATT BatteryNiCd, SAFT, 6 V, 4000 mAhLED Indicator red ID Infrared Detector Sharp GPIU901X 10 Strip fixture12 Troffer fixture 14 Emergency ballast 16 Conventional ballast 18Detector 18h Conductive case 19 Mounting bracket 20 Detector housing 22Remote Control Transmitter 23 Cable assembly 23′ Cable assembly 24Fixture lens 25 Collar section inside diameter 26 Electrical mountingtube 27 Cable 27r red cable wire 27w White cable wire 27d Drain wire 28Detector section 29 Detector section inside diameter 30 Off set 31Potting 32 Detector eye 33 Cable plug 33′ Cable plug 34 Detector shield35 Stress relieving sleeve 36 Detector/drain terminal 37 Shield/drainconnection 38 Stress relieving sleeve 40 Connection AC_(In) AC supply BCBattery charger BR Battery and relay B_(L) Lamp ballast C_(E) Variableelectronic ballast control C_(S) Switch control LAMP Lamp/lightingfixture

With the shielding offered by the described detector housing 20, thecable 23 and detector 18, all being grounded to the microcontroller RCT,the inventive signaling system may be utilized for other desirablecontrol functions in an infrared/high EMI field environment, includingfunctions as a switch for activating the standard fluorescent lamp.

The disclosed embodiments are to be considered in all respects asillustrative and not restrictive. Those skilled in the art willrecognize that variations may be made in the interrogation signal wordstyle, the sequencing, timing and phasing of the process as well asvariations in the hardware for accomplishing the test function withoutdeparting form the spirit of the invention. The scope of the inventionis to be defined by the appended claims rather than the foregoingdescriptions and other embodiments which come into the meaning and rangeof equivalency of the claims are therefore intended to be includedwithin the scope thereof.

What is claimed is:
 1. A system for controlling the off-on state of alamp, the lamp powered from a source of electrical power for providingenergy to illuminate the lamp, a switch disposed intermediate the sourceof power and the lamp, said switch operably controlled by a switchcontrol circuit remotely activated by a signal, wherein the improvementcomprises: a) a remote transmitter being programmed for sending apulse-time coded infrared signal having a carrier frequency whichexhibits a wavelength of about 770 nanometers to about 100,000nanometers for initiating a signal to the switch control circuit; b) aninfrared detector mounted adjacent the lamp for receiving saidpulse-time coded infrared signal; and c) the switch control circuitincludes a microcontroller connected to said infrared detector and tothe switch, said microcontroller being programmed to initiate a changein the state of the switch upon recognition of the pulse-time codedinfrared signal by providing an output to the switch to make or breakthe supply of power to the lamp; whereby upon actuation of the remotetransmitter, the switch control circuit causes the lamp to receive powerwhen the switch was previously off and causes the lamp to be deniedpower when the switch was previously on; and wherein saidmicrocontroller is programmed to provide an output responsive only to arepeated selected pulse-time coded infrared signal being checked forcorrectness in format based upon time, duty cycle, and matching twiceone of coded patterns generated by said remote transmitter.
 2. Thesystem for controlling the off-on state of a lamp according to claim 1wherein the carrier frequency is modulated by a sub-carrier frequency ofdigital pulses in a range of about 30 KHz to about 60 KHz.
 3. The systemfor controlling the off-on state of a lamp according to claim 1 whereinthe lamp is disposed in a lighting fixture, said infrared detector ismounted in a shielded housing disposed in the lighting fixture and theshielding of said housing is electrically connected to saidmicrocontroller.
 4. The system for controlling the off-on state of alamp according to claim 3 wherein said infrared detector is electricallyconnected to said microcontroller by a shielded cable, and said cableshielding is electrically connected to said microcontroller.
 5. Thesystem for controlling the off-on state of a lamp according to claim 4wherein said shielding of said shielded cable is electrically connectedto said shielding of said shielded housing for said infrared detector.6. The system for controlling the off-on state of a lamp according toclaim 5 wherein said infrared detector is adapted with a conductive caseand said case is electrically connected to said shielding of saidhousing and said cable shielding.
 7. The system for controlling theoff-on state of a lamp according to claim 1 wherein said lamp is anincandescent lamp.
 8. The system for controlling the off-on state of alamp according to claim 1 wherein said lamp is a fluorescent lamp.